In the Beginning...

The Lockheed P2V Neptune can trace its
maritime patrol ancestry back to the Lockheed-Vega Hudson.
The Hudson, a twin engined, twin tailed low wing aircraft,
was a bomber version of the Model 14 Super Electra airliner.
The Hudson was Lockheeds answer to a British Purchasing
Commission search for a general reconnaissance aircraft.
Design work began in 1938 and the resulting Model B14L lead
to the delivery of more than 2941 Hudsons to the UK and to
the USAAF.

Lockheed-Vegas follow up to the Model 14 was the Model
18 Lodestar. The British, well satisfied with the Hudson,
were interested in a 1939 Lockheed-Vega proposal to produce a
military version of the Lodestar. After further discussion,
the RAF ordered 300 examples of a more advanced development
of the Model 18, and christened it Ventura I. As was the case
with the Hudson, the USAAF also took delivery of 200
Venturas, designated as the B-34-VE in US service.

When Navy patrol squadrons assumed full responsibility for
antisubmarine warfare, the USAAF discontinued procurement of
the B-34 so that Lockheed-Vega could concentrate on producing
a specially configured maritime patrol version for the Navy.
The PV-1 was optimized for its primary mission with an
increased fuel capacity, modified defensive armament, the
installation of an ASD-1 search radar in the nose and could
carry eight 5-inch HVAR rockets mounted on the wings. 1600
PV-1s were delivered to the USN with many aircraft diverted
to the RAF, RAAF, RCAF, RNZAF, SAAF, and the Fôrça Aérea
Brasileira.

When the production of the Ventura was transferred from the
USAAF, the Navy and Lockheed-Vega began discussing a major
redesign of the aircraft to further tailor it for the
maritime patrol role. The Vega Model 15 had an increased wing
span, which allowed an increase in fuel capacity and an
increased bomb load. With an estimated increase in range and
improved field performance, the Navy ordered 500 aircraft
designated PV-2 Harpoon. Delivery of the Harpoons began in
March 1944. Delivery of the last PV-2D Harpoon occurred in
September 1945 bringing production of the Ventura and Harpoon
to an end. After the war, the Navy transferred Harpoons to
France, Italy, Japan, the Netherlands, Peru and Portugal.

Even before the United States entry into World War Two,
it had become apparent that the US Navy would need a
land-based patrol bomber with greater range and armament,
higher level and climbing speeds and slower approach and
landing speeds than the Hudson and Ventura. What the Navy
needed was an aircraft designed specifically for the primary
mission of day and night ASW and anti shipping operations.
Although no official requirement was issued, preliminary work
on V-135 was begun in September 1941 by chief engineer John
B. Wassall and his Vega team.

The initial concept called for
an aircraft with a gross weight of 25,000 to 35,000 lb.,
power operated turrets, tricycle landing gear and the ability
to carry two torpedoes, bombs and depth charges internally.
The favored powerplants were a pair of eighteen cylinder
Wright R-3550s producing 2000 hp. Mac V. F. Short, at the
time, Vice President Engineering of the Vega Airplane Company
authorized the first internal work order for design studies
of a new aircraft on December 6, 1941.

Progress on the new patrol plane was slow as the Navy needed
proven aircraft during the critical months following the
Japanese attack on Pearl Harbor. Eventually, by early 1943
the Navy switched its procurement attention from acquiring
immediately available aircraft, to supporting the development
of newer and more capable types. The Navy issued a letter of
intent on February 19, 1943, to the Vega Airplane Corporation
for two XP2V-1 prototypes based on the V-146 design study.
The V-146 was itself a development of the V-135 with a
revised tail, a lowered wing and a relocated dorsal turret.
Contact NOa(s)-375 was awarded on April 4, 1944 for the
construction of the two prototypes, and ten days later,
Contact NOa(s)-3297 for fifteen production P2V-1s. During
this time, the PV-2 Harpoon still had a higher priority than
the XP2V-1 in both engineering staff and floor space
allocation. It was not until the summer of 1944 that project
engineer R. A. Baily was able to get the project into high
gear.

Vega Model V-146 (XP2V-1) Proposal

The main development objective of the V-146 was to maximize
target detection and increase offensive power against those
targets. Through the use of new designs and improved
production techniques, Lockheed was able to meet the
designs need for long range, short takeoff and easy
maintenance. This design philosophy would a provide easier
production and decrease the manufacturing cost of each
individual aircraft.

One design feature was the major portion of the fuselage
contour was curved in only one direction which permitted the
use of uniformed metal skins. Expensive forming was
eliminated by producing the center wing and mid fuselage
sections, including the bomb bay door area, as a continuous
cross section. This allowed multiple use of numerous parts
and assemblies. The wing and fuselage intersection was
unfilleted, the wing box running continuously through the
fuselage. This also allowed the entire bomb bay load to be
directly distributed throughout the wings.

The Neptune was also designed to be manufactured into easily
accessible sub assemblies, keeping mating and final assembly
time to a minimum. With all of these considerations, the
Neptune became much more serviceable. A complete engine
change could be accomplished in 30 minutes, a propeller in 22
minutes and an outer wing panel in 79 minutes. The attention
to production and tooling details ensured that Lockheed would
set economic standards that would set a precedent in the
aerospace industry.

In the spring of 1945, thirteen months after the initial
contract was awarded, the Neptune was ready to fly.